Composite white pigment

Abstract

Disclosed is a composite white pigment having mixed together white pigments having different colorimeter values from each other by comprising substrates having various sizes and/or TiO2 having various thicknesses. The composite white pigment, according to the present invention, comprises: a first white pigment comprising a substrate and a white metal oxide layer formed on the substrate; and a second white pigment comprising a substrate and a white metal oxide layer formed on the substrate, and having a different colorimeter value from that of the first white pigment.

What is claimed is: 
     
       1. A composite white pigment comprising:
 a first white pigment including:
 a substrate; and 
 a white metal oxide layer formed on the substrate; and 
 
 a second white pigment including:
 a substrate; and 
 a white metal oxide layer formed on the substrate, 
 
 wherein the second white pigment has a colorimeter value different from a colorimeter value of the first white pigment. 
 
     
     
       2. The composite white pigment of  claim 1 , wherein a minimum thickness of the substrate of the second white pigment is larger than a maximum thickness of the substrate of the first white pigment by 50 nm or more. 
     
     
       3. The composite white pigment of  claim 2 , wherein a thickness of the substrate of the first white pigment ranges from 200 nm to 250 nm, and a thickness of the substrate of the second white pigment of ranges from 300 nm to 350 nm. 
     
     
       4. The composite white pigment of  claim 1 , wherein the white metal oxide layer of the first white pigment or the white metal oxide layer of the second pigment includes:
 a first high refractive layer comprising TiO 2 , wherein the first high refractive layer is on a surface of the substrate of the first white pigment or a surface of the substrate of the second white pigment; 
 a low-refractive layer comprising a material having a refractive index lower than a refractive index of TiO 2 , wherein the low refractive layer is on the first high refractive layer; and 
 a second high refractive layer comprising TiO 2 , wherein the second high refractive layer is on the low refractive layer. 
 
     
     
       5. The composite white pigment of  claim 4 , wherein when a thickness of the first high-refractive layer is T1 and a thickness of the second high-refractive layer is T2, T2>T1. 
     
     
       6. The composite white pigment of  claim 1 , wherein a minimum thickness of the white metal oxide layer of the second white pigment is larger than a maximum thickness of the white metal oxide layer of the first white pigment by 60 nm or more. 
     
     
       7. The composite white pigment of  claim 6 , wherein a thickness of the white metal oxide layer of the first white pigment ranges from 30 nm to 80 nm, and wherein a thickness of the white metal oxide layer of the second white pigment ranges from 100 nm to 160 nm. 
     
     
       8. The composite white pigment of  claim 1 , wherein the white metal oxide layer of the first white pigment or the white metal oxide layer of the second white metal oxide layer includes:
 a first high refractive layer comprises TiO 2 , wherein the first refractive layer is on a surface of the substrate of the first white pigment or a surface of the substrate of the second white pigment; 
 a low-refractive layer comprising a material having a refractive index lower than a refractive index of TiO 2 , wherein the low-refractive layer is on the first high refractive layer; and 
 a second high refractive layer comprising TiO 2 , wherein the second high refractive layer is on the low-refractive layer, 
 wherein when a thickness of the first high refractive layer is T1 and a thickness of the second high refractive layer is T2, 2T1>T2≥T1 for the first white pigment, while 3T1≥T2≥2T1 for the second white pigment. 
 
     
     
       9. The composite white pigment of  claim 4 , wherein the low-refractive layer comprises at least one selected from the group consisting of SiO 2  and MgO·SiO 2 . 
     
     
       10. The composite white pigment of  claim 1 , wherein the substrate of the first white pigment or the substrate of the second white pigment is natural mica, synthetic mica, glass flake or alumina flake. 
     
     
       11. An interference pigment comprising the composite white pigment according to  claim 1 , wherein the composite white pigment is used in at least one selected from the group consisting of paints, printing inks, floor plates, wallpaper, special paper, plastic, leather, accessories, cosmetics, ceramics and artificial marble. 
     
     
       12. The composite white pigment of  claim 8 , wherein the low-refractive layer at least one selected from the group consisting of SiO 2  and MgO·SiO 2 .